Length of pregnancy: Females typically give birth once every two to three years at the start of the winter after a gestation period of twelve months.

Range: The Blue Whale is found in every ocean except the Arctic.

Likelihood of being seen on a whale watch in Massachusetts coastal waters: Very unlikely.

Preferred food: Feed almost exclusively on small, shrimp-like creatures called krill. During the summer feeding season the blue whale eats as much as it possibly can, consuming an astounding 4 tons (3629 kilograms) or more each day. This means it may eat up to 40 million krill a day.

Unusual characteristics: The Blue Whale is the largest animal inhabiting the earth. Its heart is actually around the size of a Volkswagen Beetle. The blue whale produces louder calls than any other animal.

Appearance: The Blue Whale has a long tapered and streamlined body. The rostrum (upper part of the head) is very broad and flat, almost U-shaped, with a single ridge that extends just forward of the blowhole to the tip of the snout.

General Information: These whales are overall blue- gray color. Their dorsal fins are extremely small, and their pectoral flippers are long and thin. Blue whales can reach speeds of 35km per hour.

Unusual habits: Their throats can expand wide enough to hold 256,000 glasses worth of water. As big as they are, they are still able to breach above the water surface.

Population status: Endangered. The Antarctic sub-species is listed as critically endangered. A rough estimate of global population is 10,000 – 20,000.